Compilare: user.cpp: In function ‘void kruskal()’: user.cpp:40:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(sol.size()<n-1) ^ user.cpp: In function ‘void citire()’: user.cpp:25:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:29:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&q.x,&q.y,&q.cost); ^ user.cpp: In function ‘int main()’: user.cpp:74:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in","r",stdin); ^ user.cpp:75:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out","w",stdout); ^